Well, a "mistake" happens if you don't get what you want.
Such past "mistakes" have included the war in Iraq - which was planned by Cheney & his neocons years before 9/11.
Cheney secured all Iraq's oil wells - for his former company Halliburton, et al - within a week of the invasion. He also secured the US contracts for "cleaning up".
Billions of dollars for the military industrial complex could be called "a lucky mistake".